Cart class doesn't keep items in IE 7 & 8

[eluser]GeXus[/eluser]
I've just started using the Cart class and in IE 7 and 8, it adds items to the cart, however once I browse around the items are gone, it loses session. I know there are issues with IE and using underscores in sessions, however this is not the case I'm not using underscores. I'm also using the DB for sessions.


I've checked to make sure I'm not emptying the cart or anything and I'm not.